title: Plasma membrane mediated action of progesterone in amphibian (Rana dybowskii) oocyte maturation.
abstract: The mechanism of progesterone action within the ovarian follicle was investigated in Rana dybowskii, by using immobilized progesterone. Fluorescein isothiocyanate-labeled progesterone 3-O-carboxymethyloxime-BSA (P-BSA) was localized on the outside surface of the denuded oocyte, which indicated that P-BSA did not cross the barrier of cell surface. Progesterone-BSA induced germinal vesicle breakdown (GVBD) of denuded oocytes in a dose-dependent manner but failed to induce GVBD of follicle wall-enclosed oocytes. The time course of P-BSA-induced GVBD in denuded oocytes was similar to that observed with progesterone. Furthermore, both P-BSA and progesterone induced oocyte maturation in the presence of RU486, a well-known nuclear progesterone receptor antagonist. Treatment of denuded oocytes with P-BSA resulted in a threefold increase in inositol triphosphate (IP3) and a fourfold increase in diacylglycerol levels within 10 min. Additionally protein kinase C (PKC) activity was markedly increased by 30 min of incubation following exposure to P-BSA. Such changes were not observed in denuded oocytes exposed to beta-estradiol-6-O-carboxymethyloxime-BSA, which failed to induce GVBD. These results suggest that progesterone acts initially at the oocyte surface where it triggers generation of membrane-mediated second messengers during oocyte maturation in amphibians.
authors.affiliation: Department of Biology, Chonnam National University, Kwangju, 500-757, Republic of Korea.
authors.forename: A
authors.initials: A
authors.lastname: Bandyopadhyay
authors.forename: J
authors.initials: J
authors.lastname: Bandyopadhyay
authors.forename: H H
authors.initials: HH
authors.lastname: Choi
authors.forename: H S
authors.initials: HS
authors.lastname: Choi
authors.forename: H B
authors.initials: HB
authors.lastname: Kwon
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000502:physiology; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D005260:Female; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives / Q000494:pharmacology; D015735:Mifepristone / Q000494:pharmacology; D009865:Oocytes / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D011374:Progesterone / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism; D011898:Ranidae; D011980:Receptors, Progesterone / Q000037:antagonists & inhibitors; D015290:Second Messenger Systems / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000378:metabolism / Q000494:pharmacology*; D013739:Testosterone / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D011980:Receptors, Progesterone; C043089:estradiol 6-O-carboxymethyloxime-bovine serum albumin-fluorescein isothiocyanate; C075151:progesterone 3-(O-carboxymethyl)oxime-bovine serum albumin; C045037:testosterone-3-carboxymethyloxime-bovine serum albumin conjugate; D005576:Colforsin; D012710:Serum Albumin, Bovine; D015735:Mifepristone; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol; D011493:Protein Kinase C; D016650:Fluorescein-5-isothiocyanate